{"accessLevel": "public", "bureauCode": ["010:12"], "contactPoint": {"@type": "vcard:Contact", "fn": "Jenna A. Brown", "hasEmail": "mailto:jenniferbrown@usgs.gov"}, "description": "The U.S. Geological Survey (USGS) surveyed 7 features visible from the air to be used as ground control points (GCP) along the Delaware Atlantic coast as well as 2 reference bench marks. Global Positioning System (GPS) data were collected on July 7, 2021 in support of aerial imagery surveys documenting current topographic conditions along the coast and will be used as control and check points in Structure-from-Motion (SfM) photogrammetry processing to produce topographic maps. This dataset consists of horizontal and vertical positions of permanent GCPs, measured using Real-Time Kinematic (RTK) Global Navigation Satellite System (GNSS) equipment. The data are provided in comma-separated values (.csv) delimited text format, in projected (Universal Transverse Mercator Zone 18N) coordinates, and vertical measurements are provided as orthometric heights. Horizontal coordinates are referenced to the North American Datum of 1983 (NAD83(2011)), and orthometric heights are referenced to the North American Vertical Datum of 1988 (NAVD88), GEOID12B. Additional information as well as photographs for each GCP are also included.", "distribution": [{"@type": "dcat:Distribution", "accessURL": "https://doi.org/10.5066/P9K23VGX", "description": "Landing page for access to the data", "format": "XML", "mediaType": "application/http", "title": "Digital Data"}, {"@type": "dcat:Distribution", "description": "The metadata original format", "downloadURL": "https://data.usgs.gov/datacatalog/metadata/USGS.647e2e47d34eac007b55e39d.xml", "format": "XML", "mediaType": "text/xml", "title": "Original Metadata"}], "identifier": "http://datainventory.doi.gov/id/dataset/USGS_647e2e47d34eac007b55e39d", "keyword": ["CMHRP", "Cape Henlopen", "Cape Henlopen State Park", "Coastal and Marine Hazards and Resources Program", "Delaware", "Delaware Seashore State Park", "GPS measurement", "U.S. Geological Survey", "USGS", "USGS:647e2e47d34eac007b55e39d", "geomorphology", "geoscientificInformation", "geospatial datasets", "imageryBaseMapsEarthCover", "oceans", "topography"], "modified": "2026-03-06T00:00:00Z", "publisher": {"@type": "org:Organization", "name": "U.S. Geological Survey"}, "spatial": "-75.15868933, 38.45125245, -75.05338639, 38.78692229", "theme": ["geospatial"], "title": "Delaware Atlantic coast, 2021 - Ground Control Point Data"}